As harjun pointed out the G27 costs about twice as much as the G25,which is now a kind of a bargain.
It's really up to you but if it was my money i would have already bougt the G25 and done some mods(the one on the brake pedal,for instance,and maybe the heel and toe thing that a user is selling here
).
Yes,the G27 may be better but i wouldn't spend that much on a product that is basically the same as its predecessor.
I know that Clubsport pedals are sold for 200€,that could be an alternative if you have such money to spend as they looks really solid and adjustable.